Face masks for use in the administration of oxygen or other gases



July 24, 1962 F. G. CROASDAILE FACE MASKS FOR USE IN THE ADMINISTRATIONOF OXYGEN OR OTHER GASES 5 Sheets-Sheet 1 Filed Nov. 27, 1959 I ATTORUEYJilly 243, 11962; F. G- CRJQASDAILE' 3,045,672

FACE; MASKS FOR USE IN THE ADMINISTRATION OF OXYGEN OR OTHER GASES 3Sheets-Sheet 2 P31146612 Now 2171;. 1 959 y MMF/W ATTmeNevs July 24,1962 F. e. CROASDAILE FACE MASKS FOR USE IN THE ADMINISTRATION OF OXYGENOR OTHER GASES 5 Sheets-Sheet 3 Filed Nov. 27, 1959 JNVENTOR FwroelmlrGEQEGE Cm 01:50AM:

ATTORNEYS United States Patent 1 3,045,672 FACE MASKS FOR USE IN THEADMINISTRATION OF OXYGEN OR OTHER GASES Frederick George Croasdaile,London, England, assignor to Oxygenaire (London) Limited, London,England Filed Nov. 27, 1959, Ser. No. 855,878 Claims priority,application Great Britain July 6, 1959 I 2 Claims. (Cl. 128205) Thisinvention relates to face masks for use in the administration of oxygenand other gases, comprising a bag of flexible substantially gas proofmaterial having an open edge into which the nose and chin of a personmay be inserted.

One object of the invention is to provide a simple form of face maskcapable of being produced at a cost low enough to justify its beingdiscarded after being used only once, thus avoiding the need forsterilisation after use.

Another object of the invention is to provide a face mask having atleast one aperture connecting the interior thereof with the atmosphere,which aperture is closed by means dependent on the supply of gas to themask, so that the aperture is opened by a failure of the gas supply toensure free entry of atmospheric air into the mask and thereby avoiddiscomfort to the user owing to difficulty in breathing. i

The invention consists in the provision of a capsule in the bag of themask, which capsule is inflated by the gas supplied to the mask and,when inflated, closes a communication between the interior of the maskand the atmosphere.

In the accompanying drawings:

FIGURE 1 is a side view of one form of face mask according to theinvention;

FIGURE 2 is a section on the line 11-11 of FIG- URE 1;

FIGURE 3 is a partial elevation of the side of the mask opposite to thatshown in FIGURE 1;

FIGURE 4 is an end view looking on the open end of the mask;

FIGURE 5 is a perspectiveview showing the mask of FIGURE 1 in positionon a users face;

FIGURE 6 is an explanatory detail view corresponding to part of FIGURE2;

FIGURE 7 is a partial side View, similar to FIGURE 1, showing amodification;

FIGURE 8 is a side view similar to FIGURE 1, of another form of facemask according to the invention;

FIGURE 9 is a section on the line IXIX of FIG- URE 8;

FIGURE 10 is a partial side view of the mask shown in FIGURE 8, asviewed from the opposite side;

FIGURE 11 is an explanatory detail View similar to part of FIGURE 9; and

FIGURE 12 is a perspective view showing the mask of FIGURE 8 in positionon a u-sers face.

Referring to FIGURES l to 7 of the drawings, the mask comprises a bag 10of thin plastic material such as polyvinyl chloride, open at one edge 11and closed at its other edges. The material may be transparent, and thedrawing illustrates a mask made of transparent material.

The bag 10 is conveniently made from plastic material extruded intubular form and cut into suitable lengths, one end of each length beingshaped to form rounded corners and central projecting tabs 13, and theedges of the material at this end being heat-sealed together to closethe end of the bag, the tabs 13 forming a pocket 14 opening into themain part of the bag. At the other end' of the bag the edge of thematerial is turned inwardly and 'does not form a wall of the capsule 17,and holes 26 3,045,672 Patented July 24, 1962 ice heat-sealed at 15 tothe internal, surface of the bag, thus strengthening that edge of thebag, which remains open.

A piece of sheet material 16, similar to that of which the bag isformed, is placed between the tabs 13 and extends some distance into themain part of the bag, the extended portion being heat-sealed to one sideof the bag whilst the part which lies between the tabs 13 is sealed tothe edges of the latter. This piece acts as a membrane. The piece 16,with one tab and a part of the bag wall, thus forms a capsule -17 insidethe bag and pocket. A tubular inlet fitting 18 is heat-sealed to thepart of the bag wall which also forms a wall of the capsule, the saidfitting being adapted to receive a flexible tube for connecting the maskto a gas container or other source of gas under pressure. In theextended portion of the piece 16 there is formed an aperture '19connecting the capsule to the interior of the bag 10, the said aperture,as shown, being substantially smaller than the smallest part 21 of thebore of the inlet fitting 18.

A number of apertures 22 are formed in the side of the bag opposite tothat to which the inlet fitting 18 is attached.

A strip 23 of spongy material such as expanded plastic is secured to theinner face of one side of the bag at the open end, the strip beingshaped substantially as shown in FIGURE 4, so that, when that side ofthe bag is placed over the nose of the user, the strip fills the hollowsbetween the nose and cheeks. Alternatively, as shown in FIGURE 7, astrip 24 of ductile metal such as soft aluminum may be placed in thefold along the open edge of the bag at one side of the latter, the stripbeing mould-able to the shape of the u-sers face to keep the edge of themask in contact therewith. g A stiffening disc25 is heat-sealed to thetab 13 which forming two segments of a circle, are cut in the discs 25and the tab to which it is secured, the holes connecting the pocket 14to the surrounding atmosphere.

Two straps 27 are heat-sealed to the bag 10 so as to project from itsopen edge on the side in which the apertures 22 are formed, and anelastic cord 28 extends between the two straps 27. v

The mask is fitted to the users face by inserting the nose and chin intothe open edge of the bag, the side of the latter to which the inletfitting 18 is attached passing under theusers chin, and the elastic cord28 is passed round the back of the users head to hold the mask inposition. The strip 23 is sumciently deformable to shape itself to fitin the hollows between the nose and checks of the user and, theremainder of the edge of the bag is held against the face by the tensionof the elastic cord, so that the edge of the mask fits snugly to theface and makes a substantially gas-tight joint therewith.

If the modified arrangement shown in FIGURE 7 is used, the strip 24 ofductile metal is moulded over the users nose to shape the edge of themask to the required contour.

Oxygen or other gas to be administered is fed into the mask through theinlet fitting =18, and, since the restriction at the aperture 19 isgreater than the restriction at the inlet fitting 18 the gas passingthrough the capsule 17 into the bag inflates the capsule so as to pressthe piece 16 against the opposite wall of the pocket 14 and closing theholes 26. Flow of air or gas through the holes 26 is thus prevented, andthe user inhales gas introduced through the inlet fitting mixed with apart of the gases exhaled by him into the bag, a proportion of theexhaled gases escaping to the atmosphere through the apertures 22. Ifthe gas supply fails, the capsule 17 is de-inflated, and the holes 26are uncovered, so that the interior of the mask is able freely toreceive atmospheric air through the said holes, and the user is able tobreathe without discomfort.

The face mask shown in FIGURES 8 to 12 of the drawings comprises a bag29 made of thin sheet plastic material such as polyvinyl chloride, thematerial being first cut to a suitable shape and then folded and joinedwhere necessary by heat-sealing. The bag 29 is open at tively narrowrounded end 3 1. A portion 32 of the sheet material is folded inwardlyaround the open edge of the bag, and an extension of the folded inportion is provided, comprising a relatively narrow strip like portion33 and a substantially circular portion 34. The foldedin portion 32 isheat-sealed to the inner surface of the bag at 35 to form a tubularenclosure 36 around the open edge of the bag, and the extension is alsoheat-sealed to one wall of the bag around its edge to provide, betweenitself and that wall of the bag, a capsule 37 connected to the tubularenclosure 36 by a passage 38. The tubular enclosure 36 does not extendcompletely round the edge 30 of the bag, but is interrupted at 39 wherethe said edge, when the mask is in use, lies over the bridge of theusers nose.

A tubular inlet fitting 40, similar to that described with reference toFIGURES l to 3, is heat-sealed to the wall of the bag 29 so as to openinto the capsule 37, and an aperture 41, substantially smaller in areathan the smallest part of the bore of the inlet fitting at 42, leadsfrom the passage 38 into the interior of the bag. A stiflening .disc 43is heat-sealed to the wall of the bag opposite to that to which theextension 33, 34 is secured, so as to lie within the area of the capsule37, and a pair of segmental holes 44 are cut through the disc 43 and thepart of the wall of the bag which it covers.

Apertures 45, corresponding to the apertures 22 shown in FIGURE *1, areformed in the same Wall of the bag as the holes 44, and the mask isfitted with straps 46 and an elastic cord 47 for holding it in positionon the users face, as already described.

In the face mask shown in FIGURES 8 to 12 the incoming gas not onlyinflates the capsule 37, but also infiates the tubular enclosure 36 andthe passage 38. The inflation of the tubular enclosure 36 provides anadequate seal-between the edge 30 of the mask and the users face,

.one edge 30 and tapers inwardly from that edge to a relaand avoids theneed for the spongy material 23 or the ductile metal strip 24 describedabove. The capsule 37, when inflated closes the holes 44 as shown inFIGURE Thus the edge of the bag is held in substantial sealing relationwith the users face, and the holes 44 are closed, so long as the gas isbeing supplied. Failure of the gas supply, however, causes the capsule3'7 and the enclosure 36 to collapse. The bag will usually fall awayfrom the face when the enclosure 36 collapses, but, even if it does not,the opening of the holes 44 by the collapse of the capsule 37 allows airto enter and leave the bag freely through those holes, so that the useris not distressed by restriction of air for breathing.

I claim:

1. A face mask comprising a bag of thin flexible, substantiallygas-proof sheet material, top and bottom walls, a sealed end, and anopen end into which the nose and chin of the wearer may be inserted sothat the open end engages the wearers face, means for holding the bag inposition on the wearers face, at least one relatively large aperture inone wall of said bag connecting the interior of said bag to theatmosphere, a gas inlet in the other wall of the bag, means for closingsaid aperture when gas is flowing into said inlet, said closing meanscomprising, a thin, flexible, gas-proof membrane in said bag, saidmembrane being attached to said other wall and forming therewith acapsule, said gas inlet communicating with the inside of said capsule,an outlet opening in said capsule leading to the interior of the bag,said opening being of a smaller size than said gas inlet, whereby whengas is applied to said inlet, the flow at the outlet opening will berestricted more than at the inlet so that the capsule will be inflatedby the incoming gas closing the aperture in said bag to the atmosphere.

2. A face mask according to claim 1, wherein a disc of flexible sheetmaterial is secured to the said one wall of the bag, said aperture beingformed in the part of the said one wall within the area of the disc, acorresponding opening being formed in the disc.

References Cited in the file of this patent FOREIGN PATENTS 220,550Australia Mar. 2, 1959

